More than 20 organic molecules, including several never before detected on Mars, have been identified in soil samples by NASA’s Curiosity rover.
The findings, reported by Swedish newspaper Sydsvenskan and confirmed by multiple sources, approach from a chemical experiment using tetramethylammonium hydroxide (TMAH) performed for the first time on another world.
Astrobiologist Amy Williams of the University of Florida, who led the study, said the detected compounds include nitrogen- and sulfur-bearing molecules similar to the building blocks of life on Earth.
One identified chemical is a nitrogen-bearing molecule with a structure similar to DNA precursors; another is benzothiophene, a sulfurous compound often delivered by meteorites.
Williams emphasized that while the organics are preserved in rocks over 3.5 billion years classic, the experiment cannot determine whether they originated from ancient life or abiotic geological processes.
The study builds on earlier work begun in 2020 in a clay-rich region of Gale Crater, where clays are known to preserve organic materials on Earth.
About 500 microliters of TMAH were carried aboard Curiosity to dissolve chemicals in Martian rock, releasing gases for analysis by the Sample Analysis at Mars (SAM) instrument.
TMAH breaks apart large, complex aromatic materials into smaller components detectable by SAM, enabling the identification of the 20-plus molecules.
The researchers stressed that definitive proof of past life would require returning rock samples to Earth for laboratory analysis.
Successful use of TMAH on Mars supports plans to apply the same method in future missions, including potential exploration of Saturn’s moon Titan.
What does the detection of these organic compounds signify for the search for life on Mars?
It shows that ancient organic matter can be preserved on Mars for billions of years, which is a key factor in assessing past habitability, but it does not confirm whether life ever existed there.
Why can’t the experiment determine if the organics came from life?
The TMAH-based analysis releases molecules for identification but cannot distinguish between organic compounds formed by biological processes and those created through geology or delivered by meteorites.